It’s always good to see mainstream scientists directly addressing common myths and misconceptions about their specialty. This is especially true in medicine, because of the potential direct consequences of misinformation.

In the current issue of Sleep Health, sleep researchers surveyed websites to find 20 common sleep beliefs, and then did a literature review to find out how backed they were by published evidence. They address these common myths, and also point out questions that are still unresolved in the literature. Here are a few of the more important highlights, with some of my own experience as a physician thrown in.

In recent years, at least within my specialty of neurology, sleep difficulty has been increasingly recognized as comorbid with many of the conditions we treat. Asking patients about their sleep is now (or at least should be) routine. This is especially important because patients often do not even think about sleep as medically relevant. In my experience patients rarely volunteer information about their sleep when asked open-ended questions about their health, any problems they may be having, or anything that might influence whatever neurological problem I am seeing them for. But when I ask directly about sleep, they may tell me that their sleep is horrible and definitely worsens their symptoms. This leads me to suspect that many people just don’t see sleep as a medical issue they should discuss with their doctor, and why it is therefore so important to ask directly.

Perhaps some of the common myths exposed in this study also contribute to this phenomenon. For example, one common myth is that, “Many adults need only 5 or less hours of sleep for general health”. This is critical because some patients may only be getting 3-5 hours of sleep a night, but not perceive this as necessarily a problem. Or they nap during the day or on weekends and think this makes up for it. Perhaps their work and childcare schedule only allows for this duration of sleep and they feel they have no choice.

The reality is that chronic even mild to moderate sleep deprivation is a huge health risk factor. Chronic sleep deprivation becomes the new normal for some people and they don’t realize what an impact it is having. Often they will complain to me about symptoms of chronic sleep deprivation (poor memory, fatigue, weight gain, even excessive daytime sleepiness) and yet not connect these symptoms to their chronic poor sleep.

In reality everyone should get at least 7 hours of sleep per night. Ideally these hours should be continuous, and not interrupted or broken up throughout the day. The timing of sleep should also be as consistent as possible, to keep your brain in a 24 hour circadian rhythm.

The basic recommendations to achieve this are – no electronic devices in bed, low light is better prior to sleep to prepare the brain for sleep, get physical activity and sunlight during the day, avoid eating or drinking right before going to bed, empty your bladder before getting into bed, and address any physical symptoms that might be interfering with sleep onset or maintenance. There is more, but at this point you should probably be consulting your primary care doctor or a specialist.

Where there is enduring controversy is when trade-offs are necessary. What if you did not sleep 7 hours the night before – should you nap? Napping may make up for some lost sleep, but also breaks up your sleep cycle. So this needs to be individualized. Should you sleep in on the weekend? Same dilemma, it does make up some sleep (not completely) but shifts your circadian rhythm.

Another common myth is that a little alcohol before bed can help with sleep onset. The opposite, rather, is true. Alcohol disrupts the sleep cycle. And while we are talking about substances, caffeine is another source of sleep myths. Many people believe that as long as they restrict their caffeine to earlier in the day, caffeine will not affect their sleep.

However, having caffeine even 6 hours prior to bedtime is capable of delaying sleep onset and quality. Caffeine directly disrupts the brain’s circadian rhythm, no matter when you drink it. Further, if you have a lot of caffeine, you may be in withdrawal in the late evening or overnight, and this can cause symptoms that disrupt sleep. A good rule of thumb if you have poor sleep is to restrict caffeine to one 8 oz. beverage in the morning.

The authors also focus on snoring, which many people falsely believe is always benign. It may be, but it may also be a symptom of obstructive sleep apnea (OSA). This is a closing off of the airway due to relaxation of muscles during sleep. The evidence suggests that we are in the middle of an OSA epidemic, being driven partly by the obesity epidemic, as obesity is the major risk factor for OSA. Estimates vary between 14% and 49% of middle-aged males having OSA in the US and Europe.

OSA is a serious health problem. It increases the risk for hypertension, heart disease, and stroke. Often patients do not realize they have OSA, because they do not remember the brief awakenings that the obstructions produce. Their partner will usually know that they snore, but also not realize how severe the problem is. Patients may think they are sleeping through the night, but wake up exhausted as if they haven’t slept and have symptoms of chronic sleep deprivation.

The definitive way to diagnose OSA is with a sleep study. It is also completely treatable. The most common method is to use continuous positive airway pressure (CPAP) to keep the airway open at night. Many patients have difficulty adapting to wearing CPAP at night, but can eventually make it work. There may also be other treatment options, including surgery to widen the airway. Those with OSA are encouraged to follow up with their sleep doctor (or pulmonologist) until they have successfully treated their OSA. Weight loss, of course, may be a cure for some people, but that is a long term solution which is often difficult to achieve.

In my opinion the biggest myth of all is that poor sleep is not a medical issue. It is if it’s impaired sufficiently. There may be other underlying medical conditions causing the poor sleep also, such as OSA or even restless leg syndrome (and yes, this is a real thing). Sometimes medications may be the problem, and this needs to be reviewed with your physician. Chronic poor sleep can also occasionally be an early symptom of a more serious neurological disease.

So if you have poor sleep the first step is to dispel sleep myths. Then adopt good sleep habits. If this does not work, you have questions about what your sleep habits should be, or if you have any concerning symptoms such as severe snoring, then consult your physician.


Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also has produced two courses with The Great Courses, and published a book on critical thinking - also called The Skeptics Guide to the Universe.